Universal Plug and Play (UPnP) protocol is an emerging plug-and-play protocol for interconnecting network devices. Within UPnP, a control point may wish to respond to state changes in a network device. Eventing is the mechanism which allows control points to register for and receive notification of such state changes. Currently, an event is generated whenever there is a change in a state variable. To the extent that an UPnP service supports more than one state variable, there are no provisions for eventing on a state variable by state variable basis nor on the basis of other user customizable moderation parameters. Therefore, it is desirable to provide a more efficient mechanism for moderating event notification traffic on a state variable basis or some other user customization moderation parameter.
Due to the nature of UPnP service discovery and eventing mechanisms, UPnP technology is typically limited to network devices that are connected in a network environment where multicasting is supported. However, bridging architectures which extend UPnP technology outside of the local network are also beginning to emerge. In these instances, signaling protocols, such as SIP, may be used as the conduit for communication with mobile network devices which lie outside of the local network. Since SIP is not intended to support the high volume network traffic associated with event notification, it is further desirable to provide an event moderating mechanism which supports exporting event notification outside of the local network.